The tunneling tag has no wiki summary.
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1answer
86 views
Hawking Radiation as Tunneling
Firstly, I'm aware that Hawking radiation can be derived in the "normal" way using the Bogoliubov transformation. However, I was intrigued by the heuristic explanation in terms of tunneling. The ...
2
votes
1answer
805 views
How to solve Schrodinger Equation - Tunnelling
I have to solve analitically the Schrodinger equation in one-dimension with a barrier of potential (tunnel effect):
$$ih \frac{d}{dt} U(x,t) = \left[ \left(-h^2 \frac{d^2}{dx^2} \right) + q V(x) ...
-1
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2answers
144 views
Quantum tunneling is faster than light travel?
Quantum tunneling is faster than light travel ?
My reasoning is that the particle cannot be detected inside the tunnel so if it travels from A to B it must be instantly going from A to B , hence ...
1
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2answers
177 views
Tunneling v. Hopping
Can someone explain the difference between hopping and tunneling? The context I'm considering is conduction in semiconductors, specifically between impurity states within the bandgap. It's always ...
0
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1answer
238 views
Could Dark Matter be a manifestation of tachyons tunnelling between black holes?
Among the many Dark Matter candidates, I wondered if there are any along the lines of the title.
The inner horizon of a black hole, with its mass inflation, and/or the high spacetime curvature, seems ...
1
vote
1answer
160 views
How is quantum tunneling possible?
How is quantum tunneling possible?
According to quantum mechanics, each particle is represented by a probability density function. This function must be continuous, and therefore when we look at a ...
5
votes
3answers
609 views
Why is tunneling not a classical idea?
There is no tunneling in the case of infinite potential barrier, but there is when we have a finite well. In the classical analog, in the first case we have a particle bouncing between to infinitely ...
1
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3answers
207 views
Why is the tunnel effect of solid matter not observable in macroscopic objects?
Assume I place a tea cup on a table (say, about a centimetre thick). Quantum mechanics tells us that the wave function for the nuclei and electrons of the cup is not zero below the table (while being ...
1
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3answers
231 views
Why can't light escape from inside event horizon of Black Holes?
The simple answer: Its because Gravity of Black Hole there doesn't allow it. See also this and this Phys.SE posts.
Isn't it a classical answer? When we're unable to connect Gravity with Quantum ...
5
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2answers
127 views
Is there a time delay during tunnelling?
A particle hitting a square potential barrier can tunnel through it to get to the other side and carry on. Is there a time delay in this process?
4
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1answer
131 views
Hawking Radiation from the WKB Approximation
Reading this paper which is itself an exposition of Parikh and Wilczek's paper, I get to a point where I fail to be able to follow the calculation. Now this is undoubtably because my calculational ...
1
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2answers
170 views
Where does the “borrowed energy” come from in Alpha decay?
I was also thinking about the uncertainty principle in regards with energy & time. The question of something like:
Alpha tunneling out of the nucleus is where this can be invoked, but having an ...
4
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4answers
408 views
Where is the particle during a tunneling event?
If, say, a particle with energy $E<V_0$, approaches a finite potential barrier with height $V_0$, and happens to tunnel through, where would the particle be during the time period when it is to the ...
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0answers
87 views
Euclidean quantum gravity and gravitational instantons
I have some questions concerning the calculations made by Hawking in the 80-90's using Euclidean (canonical) quantum gravity on gravitational instantons. Were those tunnelings only between identical ...
2
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0answers
78 views
What can tunnel through a graphene sheet?
In popularizations, people tunnel through walls or doors. But what can really tunnel through a graphene sheet without tearing it?
According to Wikipedia, a single layer of graphene absorbs 2.3 % ...
1
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1answer
129 views
Can someone explain probability flux in the tunneling boundary condition of Vilenkin?
This is what's leading to the notion of a quantum universe tunneling from nothing into existence, right? The idea is that probability flux flows out of superspace (configuration space) at ...
1
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1answer
141 views
Why is Hawking's No Boundary condition described in terms of an instanton if there's no tunneling?
Regarding his take about combining No Boundary proposal with inflation theory (Hawking and Turok), he talks about the "pea instanton".
To my very limited understanding I thought instantons were only ...
5
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1answer
220 views
Chance of “macro tunneling”?
We know that subatomic particles can and do tunnel through barriers, so it is theoretically "possible" somewhat that a grain of sand could tunnel through a paper, but Id like to get some perspective ...
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7answers
1k views
Can a particle be *physically* observed inside a quantum barrier?
I understand that a particle approaching a finite potential barrier with $E < V_0$, there still is a probability of finding the particle on the other side of the barrier due to quantum tunneling.
...
5
votes
2answers
702 views
Tunneling of alpha particles
Consider this explanation of the alpha decay: It says
The Coulomb barrier faced by an alpha
particle with this energy is about 26
MeV, so by classical physics it cannot
escape at all. ...
